Bad alternator - Other Options?

[Indiana_Red@hotmail.com (Ken B)]

So my alternator light is on in my 16v transplant and I took the alt into a
chain parts store to have it tested.  The guy says as soon as he spins the
pulley  "...hear that faint scraping sound?...Diodes are rubbing.  This
thing is bad or it wont last long."  It tested at about 10.5 V and the bench
test thing was giving the diode warning light.  He must be right even if he
was kind of a jerk.  I have to other alternators.  1 has the wrong mounting
"ears" but is the 90Amp (an Ebay purchase supposedly from a Scirocco) and
the other is the 55-60A off of the 1.6 8V that the car used to have.  Is it
worth it to canibalize parts and try to rebuild this thing?  Actually if I
did I would take the op to paint the casing to match the manifold.  $120 for
a new "autolite" there more for a Bosch at NAPA or BowWow Im sure.  Looking
for less expensive options.  Could just the volt reg be replaced to fix?
Thanks as allways